Compact objects in extended scalar-tensor theories – testing further general relativity

In the present talk, we will present some very interesting solutions (neutron stars, black holes and solitons) in extended scalar-tensor theories which demonstrate the possibility to have large deviations from general relativity and still be in agreement with the current observational constraints. We focus primarily on Gauss-Bonnet theory and tensor-multi-scalar theories. The astrophysical implications, especially in the view of gravitational wave emission of such objects, as well as the prospects of imposing further constraints on the strong-field regime of gravity, are discussed as well.